commit 328432f5f45ea12a22037adff133cb253c678896
parent 33b94cd60e5951aeffd0a51e004d3626d9d9a882
Author: ThomasV <thomasv@gitorious>
Date: Mon, 31 Mar 2014 12:00:57 +0200
update bip32 derivations, using xpriv and xpub serialization format
Diffstat:
| M | lib/bitcoin.py | | | 172 | +++++++++++++++++++++++++++++++++++++++++++++---------------------------------- |
1 file changed, 99 insertions(+), 73 deletions(-)
diff --git a/lib/bitcoin.py b/lib/bitcoin.py
@@ -452,10 +452,7 @@ class EC_KEY(object):
str_to_long = string_to_number
P = generator
- if len(pubkey)==33: #compressed
- pk = Point( curve_secp256k1, str_to_long(pubkey[1:33]), ECC_YfromX(str_to_long(pubkey[1:33]), curve_secp256k1, pubkey[0]=='\x03')[0], _r )
- else:
- pk = Point( curve_secp256k1, str_to_long(pubkey[1:33]), str_to_long(pubkey[33:65]), _r )
+ pk = ser_to_point(pubkey)
for i in range(len(msgs)):
n = ecdsa.util.randrange( pow(2,256) )
@@ -524,17 +521,6 @@ class EC_KEY(object):
random_seed = lambda n: "%032x"%ecdsa.util.randrange( pow(2,n) )
BIP32_PRIME = 0x80000000
-def bip32_init(seed):
- import hmac
- seed = seed.decode('hex')
- I = hmac.new("Bitcoin seed", seed, hashlib.sha512).digest()
-
- master_secret = I[0:32]
- master_chain = I[32:]
-
- K, K_compressed = get_pubkeys_from_secret(master_secret)
- return master_secret, master_chain, K, K_compressed
-
def get_pubkeys_from_secret(secret):
# public key
@@ -545,7 +531,6 @@ def get_pubkeys_from_secret(secret):
return K, K_compressed
-
# Child private key derivation function (from master private key)
# k = master private key (32 bytes)
# c = master chain code (extra entropy for key derivation) (32 bytes)
@@ -554,7 +539,7 @@ def get_pubkeys_from_secret(secret):
# corresponding public key can NOT be determined without the master private key.
# However, if n is positive, the resulting private key's corresponding
# public key can be determined without the master private key.
-def CKD(k, c, n):
+def CKD_priv(k, c, n):
import hmac
from ecdsa.util import string_to_number, number_to_string
order = generator_secp256k1.order()
@@ -577,54 +562,107 @@ def CKD(k, c, n):
# n = index of key we want to derive
# This function allows us to find the nth public key, as long as n is
# non-negative. If n is negative, we need the master private key to find it.
-def CKD_prime(K, c, n):
+def CKD_pub(cK, c, n):
import hmac
from ecdsa.util import string_to_number, number_to_string
order = generator_secp256k1.order()
-
if n & BIP32_PRIME: raise
-
- K_public_key = ecdsa.VerifyingKey.from_string( K, curve = SECP256k1 )
- K_compressed = GetPubKey(K_public_key.pubkey,True)
-
- I = hmac.new(c, K_compressed + rev_hex(int_to_hex(n,4)).decode('hex'), hashlib.sha512).digest()
-
+ I = hmac.new(c, cK + rev_hex(int_to_hex(n,4)).decode('hex'), hashlib.sha512).digest()
curve = SECP256k1
- pubkey_point = string_to_number(I[0:32])*curve.generator + K_public_key.pubkey.point
+ pubkey_point = string_to_number(I[0:32])*curve.generator + ser_to_point(cK)
public_key = ecdsa.VerifyingKey.from_public_point( pubkey_point, curve = SECP256k1 )
-
- K_n = public_key.to_string()
- K_n_compressed = GetPubKey(public_key.pubkey,True)
c_n = I[32:]
+ cK_n = GetPubKey(public_key.pubkey,True)
+
+ return cK_n, c_n
+
+
+def parse_xprv(xprv):
+ xprv = DecodeBase58Check( xprv )
+ assert len(xprv) == 78
+ assert xprv[0:4] == "0488ADE4".decode('hex')
+ depth = ord(xprv[4])
+ fingerprint = xprv[5:9]
+ child_number = xprv[9:13]
+ c = xprv[13:13+32]
+ k = xprv[13+33:]
+ K, cK = get_pubkeys_from_secret(k)
+ key_id = hash_160(cK)
+ print "keyid", key_id.encode('hex')
+ print "address", hash_160_to_bc_address(key_id)
+ print "secret key", SecretToASecret(k, True)
+
- return K_n, K_n_compressed, c_n
+def bip32_root(seed):
+ import hmac
+ seed = seed.decode('hex')
+ I = hmac.new("Bitcoin seed", seed, hashlib.sha512).digest()
+ master_k = I[0:32]
+ master_c = I[32:]
+ K, cK = get_pubkeys_from_secret(master_k)
+ xprv = ("0488ADE4" + "00" + "00000000" + "00000000").decode("hex") + master_c + chr(0) + master_k
+ xpub = ("0488B21E" + "00" + "00000000" + "00000000").decode("hex") + master_c + cK
+ return EncodeBase58Check(xprv), EncodeBase58Check(xpub)
-def bip32_private_derivation(k, c, branch, sequence):
+def bip32_private_derivation(xprv, branch, sequence):
+ xprv = DecodeBase58Check( xprv )
+ assert len(xprv) == 78
+ assert xprv[0:4] == "0488ADE4".decode('hex')
assert sequence.startswith(branch)
+ depth = ord(xprv[4])
+ fingerprint = xprv[5:9]
+ child_number = xprv[9:13]
+ c = xprv[13:13+32]
+ k = xprv[13+33:]
sequence = sequence[len(branch):]
for n in sequence.split('/'):
if n == '': continue
- n = int(n[:-1]) + BIP32_PRIME if n[-1] == "'" else int(n)
- k, c = CKD(k, c, n)
- K, K_compressed = get_pubkeys_from_secret(k)
- return k.encode('hex'), c.encode('hex'), K.encode('hex'), K_compressed.encode('hex')
+ i = int(n[:-1]) + BIP32_PRIME if n[-1] == "'" else int(n)
+ parent_k = k
+ k, c = CKD_priv(k, c, i)
+ depth += 1
+
+ _, parent_cK = get_pubkeys_from_secret(parent_k)
+ fingerprint = hash_160(parent_cK)[0:4]
+ child_number = ("%08X"%i).decode('hex')
+ K, cK = get_pubkeys_from_secret(k)
+ xprv = "0488ADE4".decode('hex') + chr(depth) + fingerprint + child_number + c + chr(0) + k
+ xpub = "0488B21E".decode('hex') + chr(depth) + fingerprint + child_number + c + cK
+ return EncodeBase58Check(xprv), EncodeBase58Check(xpub)
-def bip32_public_derivation(c, K, branch, sequence):
+
+def bip32_public_derivation(xpub, branch, sequence):
+ xpub = DecodeBase58Check( xpub )
+ assert len(xpub) == 78
+ assert xpub[0:4] == "0488B21E".decode('hex')
assert sequence.startswith(branch)
+ depth = ord(xpub[4])
+ fingerprint = xpub[5:9]
+ child_number = xpub[9:13]
+ c = xpub[13:13+32]
+ cK = xpub[13+32:]
sequence = sequence[len(branch):]
for n in sequence.split('/'):
- n = int(n)
- K, cK, c = CKD_prime(K, c, n)
+ if n == '': continue
+ i = int(n)
+ parent_cK = cK
+ cK, c = CKD_pub(cK, c, i)
+ depth += 1
+
+ fingerprint = hash_160(parent_cK)[0:4]
+ child_number = ("%08X"%i).decode('hex')
+ xpub = "0488B21E".decode('hex') + chr(depth) + fingerprint + child_number + c + cK
+ return EncodeBase58Check(xpub)
+
- return c.encode('hex'), K.encode('hex'), cK.encode('hex')
def bip32_private_key(sequence, k, chain):
for i in sequence:
- k, chain = CKD(k, chain, i)
+ k, chain = CKD_priv(k, chain, i)
return SecretToASecret(k, True)
@@ -642,41 +680,28 @@ def test_bip32(seed, sequence):
see https://en.bitcoin.it/wiki/BIP_0032_TestVectors
"""
- master_secret, master_chain, master_public_key, master_public_key_compressed = bip32_init(seed)
-
- print "secret key", master_secret.encode('hex')
- print "chain code", master_chain.encode('hex')
-
- key_id = hash_160(master_public_key_compressed)
- print "keyid", key_id.encode('hex')
- print "base58"
- print "address", hash_160_to_bc_address(key_id)
- print "secret key", SecretToASecret(master_secret, True)
+ xprv, xpub = bip32_root(seed)
+ print xpub
+ print xprv
+ #parse_xprv(xprv)
- k = master_secret
- c = master_chain
-
- s = ['m']
+ assert sequence[0:2] == "m/"
+ path = 'm'
+ sequence = sequence[2:]
for n in sequence.split('/'):
- s.append(n)
- print "Chain [%s]" % '/'.join(s)
+ child_path = path + '/' + n
+ if n[-1] != "'":
+ xpub2 = bip32_public_derivation(xpub, path, child_path)
+ xprv, xpub = bip32_private_derivation(xprv, path, child_path)
+ if n[-1] != "'":
+ assert xpub == xpub2
- n = int(n[:-1]) + BIP32_PRIME if n[-1] == "'" else int(n)
- k0, c0 = CKD(k, c, n)
- K0, K0_compressed = get_pubkeys_from_secret(k0)
-
- print "* Identifier"
- print " * (main addr)", hash_160_to_bc_address(hash_160(K0_compressed))
- print "* Secret Key"
- print " * (hex)", k0.encode('hex')
- print " * (wif)", SecretToASecret(k0, True)
+ path = child_path
+ print path
+ print xpub
+ print xprv
- print "* Chain Code"
- print " * (hex)", c0.encode('hex')
-
- k = k0
- c = c0
print "----"
@@ -709,7 +734,8 @@ def test_crypto():
if __name__ == '__main__':
- test_crypto()
- #test_bip32("000102030405060708090a0b0c0d0e0f", "0'/1/2'/2/1000000000")
- #test_bip32("fffcf9f6f3f0edeae7e4e1dedbd8d5d2cfccc9c6c3c0bdbab7b4b1aeaba8a5a29f9c999693908d8a8784817e7b7875726f6c696663605d5a5754514e4b484542","0/2147483647'/1/2147483646'/2")
+ #test_crypto()
+ test_bip32("000102030405060708090a0b0c0d0e0f", "m/0'/1/2'/2/1000000000")
+ test_bip32("fffcf9f6f3f0edeae7e4e1dedbd8d5d2cfccc9c6c3c0bdbab7b4b1aeaba8a5a29f9c999693908d8a8784817e7b7875726f6c696663605d5a5754514e4b484542","m/0/2147483647'/1/2147483646'/2")
+
